In the area of providing means for transferring ink from a ribbon to record media, it is well known that impact-type printing or recording has been utilized since the earliest recording machines. The typewriter and the character printer are most common in the field of impact operation.
More recently, non-impact type apparatus has appeared in the printing and recording field and wherein the most common have been the thermal printer and the ink jet printer. When the performance of a non-impact printer is compared with that of an impact printer, one of the problems in the non-impact machine has been the control of the printing operation. As is well known, the impact operation depends on the movement of impact members such as wires or the like and which are typically moved by means of an electromechanical system which is believed to enable a more precise control of the impact members.
The advent of non-impact printing, as in the case of thermal printing, brought out the fact that the heating cycle must be controlled in a manner to obtain maximum repeated operations. Additionally, the non-impact printing operation may utilize components wherein the method is simple in operation, the transfer of ink from a ribbon to the record media is more refined or precise, and also different types of font printing can be realized.
Known methods of non-impact printing are based on ink transfer from the ribbon to the paper by means of a single component laser beam or by means of a modulated laser beam. In one instance, a focused laser beam causes the thermal transfer of ink or dye from a coated plastic ribbon to the paper. One explanation of the theory of transfer of ink provides that the laser irradiation of the substrate-ink boundary creates thermal elastic stress waves which cause the transfer of the ink or dye. Another explanation of the theory of transfer is that high density thermal energy melts and vaporizes the wax-like ink and the printing or recording is formed upon condensation of the ink or dye vapors on the lower temperature paper.
In the prior art, it is known that one of the line printers which utilizes the focused laser beam technique is designed for printing characters in a five mil density dot matrix by nineteen horizontal scans of laser beam per character.
In a number of inks being tested, there has been no indication of using a magnetic ink ribbon. It could be foreseen that a large problem in the transfer of ink containing magnetic particles is the difficulty in matching spectrosensitivity with available laser apparatus and that the cost may be prohibitive if expensive energy sources must be used.
It is therefore proposed to provide means for transferring magnetic ink from the ribbon to the paper by use of a pulsed light source and focusing the characters on the paper.
Representative prior art in the field of non-impact printing by use of thermal energy include U.S. Pat. No. 3,131,302 issued to D. G. Kimble on Apr. 28, 1964, which discloses thermoprinting by preheating the original image and front printing on heat-sensitive copy paper.
U.S. Pat. No. 3,176,278 issued to L. J. Mayer on Mar. 30, 1965, discloses a thermal method and system of magnetic recording.
U.S. Pat. No. 3,314,073 issued to C. H. Becker on Apr. 11, 1967, discloses a laser recorder with vaporizable film and including laser means focusing the laser on the coating to cause removal of bits of coating in proportion to the modulated laser thermal energy and means for moving the film past the focus point.
U.S. Pat. No. 3,351,948 issued to T. H. Bonn on Nov. 7, 1967, discloses a laser recorder using a medium having encapsulated chemicals and a source for generating a high energy beam and a low energy beam.
U.S. Pat. No. 3,570,380 issued to B. Kamenstein on Mar. 16, 1971, discloses an impactless typewriter wherein a light source is used to illuminate a thermographic material through a character-shaped aperture in a mask. The light source generates heat in the thermographic material to cause it to be transferred in the character shape to a receiving substrate.
U.S. Pat. No. 3,662,397 issued to D. O. Ballinger on May 9, 1972, discloses a thermal sensitive recording medium having reflective particles responsive to a magnetic or an electrostatic field and heat is utilized to fix a recording trace on the medium.
U.S. Pat. No. 3,703,143 issued to J. Gaynor on Nov. 21, 1972, discloses a thermal transfer sheet having a discontinuous layer of transfer material and a method of thermally transferring images.
U.S. Pat. No. 3,744,611 issued to L. Montanari et al. on July 10, 1973, discloses an electrothermic printer which has a ribbon with a thermal transferable ink coated on one surface and a coating of electrically resistive material on the other side. The ribbon is in contact with the paper while electrodes are energized to cause current to pass through a portion of the resistive material and to heat the coating of ink. The ink transfers to the paper as a dot or a line.
U.S. Pat. No. 3,985,439 issued to H. Kiemle on Oct. 12, 1976, discloses a device for light optical computer controlled drawing of masks for semiconductor components with a modulated light beam and a lens arrangement for projecting the light onto a layer of light-sensitive material disposed on a plane of a carrier to form a mask pattern. U.S. Pat. No. 4,125,842 issued to M. Ohnishi et al. on Nov. 14, 1978, discloses a method for laser recording using modulated laser light and a heat-sensitive recording material.